Damage detection in Armored Vehicle Launched Bridge (AVLB)

AVLB stands for Armored Vehicle Launched Bridge. A system was designed for performing damage detection and localization in AVLB using vibration data. Specifically, the damage detection method was based on a modified method of strain energy mode shapes.

Video on the bottom of this page shows the system in action.

The bridge was installed on airbags and excited by band-limited white noise. A scanning laser vibrometer was installed on a robotic gantry crane and could be positioned at any location above the bridge with accuracy of 5mm. A frequency response function (FRF) was computed between excitation measured by a force transducer and response of the bridge. A grid of points was scanned along each girder and displacement (bending) modeshapes were computed for the bridge. Then signal processing and a fuzzy expert system identified possible damage and its location.

Video of AVLB damage detection system

Publications

Optimal spatial sampling interval for damage detection by curvature or strain energy mode shapes

Non-baseline detection of small damages from changes in strain energy mode shapes

Fuzzy logic expert system for automated damage detection from changes in strain energy mode shapes

Automated Laser Sensor System

Non-baseline damage detection from changes in strain energy mode shapes. Experiments on Armored Vehicle Launched Bridge

Genetic Algorithms-Based Parameter Optimization of a Non-Destructive Damage Detection Method

Enhancing accuracy of data acquired by a laser vibrometer in a field setting